Device for refueling a gaseous fuel tank

Abstract

A compressor (1) can be connected on the suction side via a suction line (7) provided with an inlet valve (16) to a natural gas line (9) and on the pressure side via an intake line (12) to the gas fuel tank (13) and is also connected via a relief line (10) to a relief valve (11) and a pressure control valve. (25), with said valves being disposed in a pressurized tank (4). This tank is connected to the suction side of the compressor (1) and the outlet sides of the inlet valve (16) and of the relief valve (11) and also with an outlet line (18) via a safety valve (20), which can be set at a predetermined opening pressure of 2 to 3 bar, for example. The pressurized tank (4), is designed with a cover (5) constructed as a support part, on which the compressor (1) is mounted. The compressor (1) can be coupled via a vertical drive shaft (2) with a motor (3) disposed inside the pressurized tank (4). This arrangement permits a simple design of the pressurized tank (4) and a compact construction of ,the appliance, which is particularly intended for refueling motor vehicles.

We claim: 
     
       1. An appliance for refueling a gas fuel tank (13), having a compressor (1) which can be driven via an electric motor (3), the suction side of which can be connected via a suction line (7) provided with an inlet valve to a source of the gas fuel, more especially a natural gas line (8), and the pressure side of which can be connected to an intake line (12), which can be coupled with the gas fuel tank (13) to be refueled, and is connected to an outlet line (18) leading out of the pressurized tank (4) via control and monitoring elements, which contain a relief valve disposed in a pressure chamber of a pressurized tank (4) and a safety valve (20), which can be set at a predetermined opening pressure, characterized in that the suction side of the compressor (1) and the suction line (7) are connected to the pressure chamber of the pressurized tank (4) containing the relief valve and the safety valve (20), in that the outlet line 18) is connected via the safety valve (20) to this pressure chamber, and in that a part of the pressure chamber (4) is constructed as a support for a housing part (1a) of the compressor (1) which can be mounted thereon. 
     
     
       2. An appliance according to claim 1, characterized in that the support has an aperture (19) which can be sealed with respect to the housing part (1a) of the compressor (1), and in that the motor (3) is disposed on the side of the support remote from the compressor (1) and can be coupled to the compressor (1) via a drive shaft (2) penetrating this aperture (19). 
     
     
       3. An appliance according to claim 1, characterised in that the compressor (1) is disposed on the outside of the support, in that the stator (64) of the motor is fixed to the inside of the support, and in that the rotor (65) of the motor 3) is connected to the drive shaft (2) of the compressor (1) to form a mounting unit which can be inserted through aperture (19) into the stator (64). 
     
     
       4. An appliance according to claim 1, having control and monitoring components, which are connected via electric lines (30, 31, 33, 34, 40, 41) to a control appliance (32), characterized in that the control appliance (32) is disposed outside the pressurized tank (34), and in that the support is designed with connections (67, 68, 70 and 71) for the suction line (7), the outlet line (18) and a relief line (10) leading to the relief valve and also for the electrical lines (30, 31, 33, 34, 40, 41). 
     
     
       5. An appliance according to claim 1, having an approximately cylindrical pressurized tank (4), characterized in that the support is formed by a cover (5) of the pressurized tank (4) and in that the pressurized tank (4) and the compressor (1) are disposed with an approximately vertical longitudinal axis (B) or vertical drive shaft (2) respectively and are lodged in a housing (46) surrounding them which is suitable for air conduction, and which is provided with an inlet aperture (50) at the lower end and with an outlet aperture (52) for cooling air at the upper end and which, at least with the pressurized tank (4), limits an annular duct (51), through which the cooling air flows and which is open towards the compressor (1) and the outlet aperture (52). 
     
     
       6. An appliance according to claim 5, characterized in that in the region of the inlet aperture (50) is disposed a fan (36) with an impeller which can be driven around a vertical axis, and in that in the region of the cover (5) of the pressurized tank (4) guide means are permitted to deflect the cooling air flowing around the pressurized tank (4) towards the housing part (1a) of the compressor (1) connected to the cover (5). 
     
     
       7. An appliance according to claim 6, characterized in that the housing (46) is designed with a deflector plate (77) like an annular disc which is disposed at an axial distance from the cover (5) of the pressurized tank (4) and which covers its outer edge part, and in that guide elements similar to guide blades are provided as guide means for the cooling air. 
     
     
       8. An appliance according to claim 7, characterized in that the guide elements are formed by fins (78) which are constructed on the cover (5) and extend from its peripheral region towards aperture (19), and which are involutely curved. 
     
     
       9. An appliance according to claim 5, characterized in that the housing (46) surrounding the pressurized tank (4) and the compressor (1) is disposed inside an outer housing (85), which contains an inlet aperture (91) and an outlet aperture (92) for the cooling air and which with the inner housing limits two partial chambers (89 and 90) separated by partitions (88) and through which cooling air can successively flow, one of which (89) connects the two inlet apertures (50 and 91) and the other of which (96) connects the two outlet apertures (52 and 92) of the housings (46 and 85). 
     
     
       10. An appliance according to claim 9, characterized in that the control appliance (32) is disposed between the inner housing (46) and the outer housing (85). 
     
     
       11. An appliance according to claim 1, having a pressure control valve (25) which is connected to the pressure side of the compressor (1) and can be set at a predetermined maximum pressure of the gas fuel, characterized in that the pressure control valve (25) is disposed in the housing of the compressor (1) and is connected to a duct (10b) connecting the pressure side and the suction side of the compressor (1). 
     
     
       12. A device according to claim 1 including a duct fluidly connecting the pressure side of the compressor with the suction side and a pressure control valve preventing fluid communication through the duct until the pressure has reached a predetermined value. 
     
     
       13. A gaseous fuel refueling system for filling a gas tank with gaseous fuel under pressure, the system comprising a self-supporting pressure tank defining a pressure chamber and including means for connecting the chamber to a source of gaseous fuel, a vent communicating the chamber with an exterior of the tank, and gas flow control means including a relief valve and a safety valve disposed within the chamber; a compressor unit comprising a compressor and an electric motor for driving the compressor, the compressor including a suction side and a suction line fluidly connecting the suction side with the pressure chamber and therewith with the fuel source, and a pressure side in fluid communication with a gaseous fuel intake line for the gas tank and the relief valve for selectively communicating the pressure side with the pressure chamber and thereby with the vent when the safety valve is in its open position; whereby, upon activation of the electric motor, the compressor draws gaseous fuel from the chamber and, in response to a predetermined condition, compressed gaseous fuel discharged at the pressure side of the compressor can be vented via the gas flow control means, the pressure chamber and the vent to the exterior of the tank; the tank further including means for fully supporting the compressor. 
     
     
       14. A device according to claim 13 wherein the compressor unit includes a shaft connected to the motor and the compressor and axially spacing them apart, and wherein the means for supporting comprises means rotatably mounting the shaft to the tank, positioning the motor in the chamber and the compressor on the exterior of the tank, and sealing the pressure chamber from the exterior. 
     
     
       15. A device according to claim 14 wherein the motor includes a stator secured to the means for supporting and located in the chamber and a rotor, the rotor and the compressor being secured to the shaft to form a shaft unit adapted to be operatively coupled with the stator to form the compressor unit by moving the rotor and therewith the shaft and the compressor in an axial direction from the exterior of the tank until the rotor is in registration with the stator. 
     
     
       16. A device according to claim 13 including an electronic control unit for sensing conditions in the chamber and for operating the flow control means, an electronic control appliance mounted on an exterior of the tank, and electric leads operatively coupling the control unit with the electronic control appliance; and wherein the means for supporting defines means for fluidly connecting the chamber with the suction line, the pressure side and the vent means for passing the electric leads from the chamber to the exterior. 
     
     
       17. A device according to claim 13 wherein the tank includes an upwardly open, cylindrical main portion, and a cover covering the main portion and wherein the cover defines the support. 
     
     
       18. A device according to claim 17 wherein the compressor is disposed on an exterior of the tank, and including an inner housing mounting the tank so that an axis of the electric motor is substantially vertically oriented, the inner housing including means for inducing a controlled flow of cooling air about portions of the exterior of the tank and flow channeling means between the tank and the inner housing directing the induced cooling air flow towards cooling surfaces of the compressor. 
     
     
       19. A device according to claim 18 wherein the flow channeling means includes an annular disc disposed between the tank cover and the inner housing having spirally-shaped blades extending from a vicinity of an annular space between the tank and the inner housing to a vicinity of the compressor along an involutely curved path. 
     
     
       20. A device according to claim 18 wherein the means for inducing a controlled flow includes an inlet to an interior of the inner housing proximate a lower end thereof, and including an outer housing surrounding the inner housing, means mounting the inner housing to the outer housing to define an annular space between them in fluid communication with the inlet of the inner housing, and means dividing the annular space into first and second portions which are sealed from each other and which fluidly connect the inlet with only one of the two portions, an intake opening communicating said one of the two portions with the exterior of the outer housing, and an outlet in the outer housing communicating the other portion with the exterior of the outer housing so that cooling air can flow through the intake opening, the first portion, the inlet, the other portion and the outlet to the exterior again.